Reservoir assemblies of various types are known in the art, for example vials, prefilled syringes, disposable pen-type injectors, cartridges for reusable injectors, etc. For certain applications it may be necessary to apply tow or more medicaments at the same time. Under certain circumstances, the two medicaments cannot be stored in a single reservoir or container for incompatibility reasons, or the like. Thus, storage in separate reservoirs is necessary. However, it may be required that during administration, the two medicaments from the separate reservoirs be delivered at the same time and in a single injection step.
Co-delivery of two medicaments is known in the art. WO 2010/139676 A1 discloses a medicated module for an injection system to co-deliver at least two medicaments, where a primary delivery device containing a primary medicament accepts a medicated module containing a single dose of a secondary medicament contained within a capsule having an integral flow distributor/distribution system and where both medicaments are delivered through a single hollow needle. The flow distributor may minimize stagnant flow of the medicament and promote/maximize plug flow of the medicament through the capsule and out of the medicated module.
A user of such a system would have to provide the force to expel the primary medicament from the device and the secondary medicament from the capsule of the module. Therefore, the required force may be too high for a user. In addition, the increased pressure may be mistakenly perceived by a user as a malfunction of the system, e.g. an occlusion of the delivery channel.
It is thus an object of the present invention to provide a reservoir assembly, a drug delivery device, and methods for actuating the same, featuring an improved delivery mechanism. It is a further object to provide unambiguous support for a user in handling and/or operating a drug delivery system for co-delivery of at least two medicaments.